Fabric cutting device for cutting fabric in circular knitting machines



Aug. 25, 1970 PlANA ET AL 3,525,24Q

FABRIC CUTTING DEVICE FOR CUTTING FABRIC IN CIRCULAR KNITTING MACHINES Filed March 24, 1969 2 Sheets-Sheet 1 INVENTOR. FRANCESCO PIANA BY ANGELO BREGA A G E T Aug. 25, 1970 p A ET AL 3,525,240

FABRIC CUTTING DEVICE FOR CUTTING FABRIC IN CIRCULAR KNITTING MACHINES Filed March 24, 1969 2 Sheets-Sheet 2 IN YENTOR;

FRANCESCO PKANA ANGELO BREGA United States Patent O 3,525,240 FABRIC CUI'IING DEVICE FOR CUTTING FABRIC IN CIRCULAR KNITTING MACHINES Francesco Piana and Angelo Brega, Varese, Italy, assignors to MECMOR S.p.A., Milan, Italy, a corporation of Italy Filed Mar. 24, 1969, Ser. No. 809,618 Claims priority, application Italy, Mar. 27, 1968, 14,450/ 68 Int. Cl. D04b 35/34 US. Cl. 66147 2 Claims ABSTRACT OF THE DISCLOSURE This disclosure relates to a fabric cutting device for cutting fabric in circular knitting machines, comprising a shears unit having a movable blade supported on a support body which is slidably mounted on guide means arranged within the needle cylinder and under the crown of a circular knitting machine, electromagnetic means being provided for cyclically operating said movable blade so as to cut the knitted fabric into longitudinal strips of predetermined Width.

BACKGROUND OF THE INVENTION This invention relates to a fabric cutting device for the cutting of fabric in circular knitting machines. In particular this invention relates to a fabric cutting device for cutting fabric in circular knitting machines in which the needle cylinder and the crown are fixed while the reel and the locks turn.

It is well known that for some time knitting machines of the above type have been available, both completely circular (tubular) and circular but not completely closed. The knitted fabric produced by these machines is only rarely utilised in its complete width as determined by the diameter of the cylinder of the knitting machine, and more frequently it is cut longitudinally into dimensions which are closer to those of the knitted articles which are to be made from the fabric. The cutting operation, in addition to being rather laborious and requiring the use of other machines or devices and personnel to operate them, frequently results in wastage of fabric which can be considerable and consequently economically disadvantageous.

The main object of this invention is that of providing a fabric cutting device for use with knitting machines of the described type which allows the mentioned disadvantages to be completely obviated and which is appropriate to the present level of technology, in other words to provide a cutting device of automatic operation which is such as to ensure a longitudinal cut in the fabric as it is being produced, according to predetermined dimensions.

Another object of this invention is that of providing a fabric cutting device of the described type, whose structural characteristics are such as not to complicate the structure or alter the operation or efiiciency of the knitting machine to which it is to be applied.

A further object of this invention is that of providing a fabric cutting device having a simple structure, of easy and general application to knitting machines, comprised of parts or devices of simple construction and of practical and reliable operation.

SUMMARY OF THE INVENTION These and still further object which will appear hereinafter, are attained by a cutting device according to the invention which comprises a shears unit including at least one movable blade supported by a support body which is slidably mounted on a circular guide rail secured 3,525,240 Patented Aug. 25, 1970 BRIEF DESCRIPTION OF THE DRAWINGS Further characteristics and advantages of the invention will become clear from the detailed description of a preferred, but not exclusive embodiment of a cutting device according to the invention, illustrated by way of example in the accompanying drawings in which:

FIG. 1 shows a lateral diagramatic view of a cutting device according to the invention applied to a circular knitting machine;

FIG. 2 shows a partial plan view of FIG. 1;

FIG. 3 shows a perspective view of a cutting device according to the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the above figures, the cutting device according to the invention comprises a shears unit 1 which comprises a movable blade 2 secured to the core 3 of an electromagnet 4. Said shears unit 1 and said electromagnet 4 are supported on a platform 5 which is rigidly fixed to the top of a saddle 6. This saddle 6 is engaged to slide (see FIG. 2) on a circular guide rail 7 located inside the fixed needle cylinder 8 and below the fixed crown 9 of a circular knitting machine. Said guide 7 is supported by the fixed part 10 of said machine, by means for example of a double angle bracket 11, and carries a pair of electrical contacts 13 and 14 with the interpositioning of a spacer 12 of electrical insulating material, said contacts running concentrically with the rail itself. The saddle 6 is furnished with a pair of pins 15 and 16 which, at one end, are constantly in contact with said pair of electrical contacts 13 and 14 and, at the other end, form terminals which are connected electrically by cables 17 to the terminals 18 and 19 of said electromagnet 4.

A microswitch 21 is secured to the base 20 of said knitting machine and controls the supply of electrical energy to said pair of circular contacts 13 and 14. This microswitch 21 is activated by a rod-like element 22 which is subject to the action of a spring not shown in the figure. A disc 23 is secured to the rotating part 24 of said knitting machine and is positioned so as to engage the push button end 25 of said rod-like element 22. When this happens the rod-like element, moving against the action of the spring, closes said microswitch 21.

The working of the fabric cutting devices is as follows. By slackening the bolt 26 of the saddle 6, said saddle is positioned on said guide rail 7 so that the shear-like member 1 is made to act on the fabric (diagramatically shown at 27) at the desired position.

At this point the knitting machine is started. At each turn of the rotating portion of said machine, the disc 23 will cause the microswitch 21 to close, and this will cause the supply of electrical energy to the pair of contacts 13 and 14. In this way the electromagnetic 4 will be energised with movement of the relative core 3, which causes the operation of the movable blade of the shear-like device, so obtaining the desired cut in the lengths of fabric being produced. A further disc 23 can be advantageously provided diametrically opposed to that previously described, its presence being such as to cause the microswitch 21 to give two impulses for every revolution, correspondingly doubling the frequency of the cutting action.

Particular mention should be given to the possibility of arranging the cutting device in the preferred position corresponding to the widths of the length of knitted fabric as required. A further very evident advantage consists of the economy of production which said device allows.

We claim:

1. A fabric cutting device for the cutting of fabric in circular knitting machines, which comprises a shears unit including "at least one movable blade, supported by a support body arranged slidably on a circular guide rail secured to the fixed structure of the knitting machine and positioned inside the needle cylinder and under the crown, a pair of electrical contacts fixed to said guide rail and in electrical contact with electromagnetic means acting on 15 said movable blade of said shears unit, means for controlling the periodic feeding of electrical energy to said electrical contacts and releasable locking means for locking said support body onto said guide rail.

2. A fabric cutting device as claimed in claim 1, in which said means for controlling the periodic supply of electrical energy to said electrical contacts comprise a microswitch activated by a rod-like element and fixed to the fixed structure of said knitting machine, and at least one substantially disc-like element fixed to the rotating part of said knitting machine and arranged to act periodically on said rod-like element.

References Cited UNITED STATES PATENTS 1,007,629 10/ 191 1 Ballard 66 28 2,447,103 8/1948 Susen 66-147 XR 2,515,687 7/1950 Bausher et a1. 66147 FOREIGN PATENTS 483,197 7/ 1953 Italy.

WM. CARTER REYNOLDS, Primary Examiner 

